Process of making sodium sulphide



EUREEJiPuB ALVQIQJ), GTE GLEVELAIPUJ, SKIS, AfiSISN 3P9 THE GRJKEEETBILLE GEFEME GQIIlIY-PANK', 03F CLEVELAHD, SE10, A GQPZ-PGRATIGIQ' OF SE).

2% .eppiiesticn' files may whom ii mcuy co lwemr known 'ihflt Essi- BUEHABD AL- voun, ciiizeii mi "J Suites, residing eucl, in ulie county of Guyulioge of Ohio, have invented certaiunew dil'Cl Stat and useful EIBQXOVQIDQIZlLS in Processes of Ella-kins Sodium Sulpliicle of which the fol lowiug is specification.

in the process counuouly employed for the -whereby the imgi'urities including sodium manufacture of sodium sulphide on u comi'ueiiciul scale sodium. sulfate is reduced to the sui liicle usually by heating a, mixture of soul. ii sulfate and coal. iii furnace, Til?) ifui'uece produce is an inioure mixture couiuining uxicliaugeel sodium sulfate, unconsumed fuel ash from the fuel, secondary goi'oducis of the reaction such us, sodium oer boiiute u-mi sodium 'liyposuliiie and varying quantities of sodium sulphide, Sodium sul-- Qllldfi is recoveizcd from the furnace product by leaching. One of the disalvuntages of this process is the low yield of sodium sulphide, which may be uttributed to incomgilete reaction, secondary iceoctions and loss oi. sodium sulphide incidental to the semiei'y of sodium sululiicle from the furnace product.

in an application entitleil Process of inelisodiuin sulphide, filed by Henry Howard on March 1922;, Serial No. 5%,186, is described e process of making sodium sulphide by treutiiig solutious containing the some and sodium cerbonaie such as the ciucie solutions of sodium sulphide formed by caching (luced.

black ash Wll'll lime and hydrogen whereby the sodium carbonate coniliereof is converted. to sodium sulphide.

l have found that, the mentioned lieutiueut Wit'li lime and hydrogen sulphide for the conversion of sodium carbonate content of a sodium" sulphide solution so sodium sulphide may also serve to convert sodium sulfate anilotlier sodium salts, l lie acid radicals of which are capable of forming Wfltfil? iusolublesslis with calcium, to sodium sulpi icle, and my invention therefore relates to she pi'oeluctiou of sodium sulpliide from impure solutions thereof containing such sodium salts by the treatment thereof Willi lime liyiliogeii sulphide.

The process is purfiiculurly applicable for the recovery of sodium sulphide i'yom (lilute solutions or liquors containing sodium sul leis; wiicli other sodium salts which cannot lee i'esdily separated irom she sodium sulcei'bonate, sodium sulfate, and. sodium hyposulfite ei'eleft in the uuclissolvecl residue along with u consicleralole proportion of the sodium sulphirle content of the black ask. it is customary to further leech this residue with relatively large amount of Water to separate lzhe soluble sodiu n salts from the fuel and ash whereby dilute solutions containing sodium sulphide, soclium carbonate, sodium sulfate encl small. amounts of other sells such as sodium hyposulfite' are proll/ietliofls now known for the recov cry of sodium sulphide from such solutions ere nos satisfactory and the solutions are either Wasted or useal for some other purposes w l have found that sodium sulphicle in commercially pure form may be economically recovered from dilute solutions of sodium sulphide containing sodium sulfate or sodium sulfate and carbonate by an application of my process as follows:

To the dilute solution coutuiuiiip' sodium sulphide and sodium sulfate 01 sulfate and carbonate is uclclecl lime in quantity theoi'eticully sufficient to convert the sorlium sells other than the sulphicle to sodium hydroxicl. The conversion of sodium salts to the liydroxid by reaction with lime is not complete. Hydrogen sulphide is then ecltlecl to the solution either in gaseous form or in the oi-in of a solution in Wuter'us a result of which the sodium liydroxid is converted 1'0 sodium sulphide. Sodium hydroxid be-. ing removed from the sphere of reaction the reaction beoween lime and the sodium salts forming sodium hyclioxicle proceeds sub stantially to completion. When sufioient hydrogen sulphiole has been added to convert the sodium hydioxicl to sulphide, that is, a quantity chemically equivalent to the quantity of lime added, the solutionis seemteol from the precipitate of calcium sulieie or carbonate or e mixture of the two oepencling upon Whether the solution coir mined sodium carbonate or suit-fete or both. This purified solution couiuius ell off time .iie of the original impure soaddition the sodium sulphide ii: the purifying pr-mess. Sodium e is recovaroo by evaporation or 1 in the Well known mazmexx sol; containi sodium. 51, fate ooh con -I flaming such soluiions wun 10 lime. @111 hydloven sulphide in quantity ui ficiont to com ort the sodium sulfate to so (hum sulphide,

2w Process of purifying soiuticms of dimn sulphide conta b1 zo'iium carbonate v oi EGUlif iB solutions soin z sog sodium sulfate 1 comprlsao .m

such solutions with 352119, in

ficient to combine with the oarboim suifmo and with hydrogen sul ohieio in quantity chemioaliy equiv-idem to said Process oi yunfymg Solomons so Gium suiphide produced by leaching and with hydrogen sulphide in. qu tity ial she nioally eqplvzzlent to said lime:

i afiix my signalavLer-Jnsolubla calcium comyounds 

